Steam-engine pressure-recorder and speed-indicator



(No Model.)

G. W. BROWN. STEAM ENGINE PRESSUREA RECORDER AND SPEED INDICATOR. No.316,111.

Patented Apr. 21, 1885.`

N. PETERS. mmxwmugmpnef. whingwrn. c.

UNTTED STATES PATENT Ormes@ GILMAN VELD BROVN, OF VEST NEWBURY, ASSIGNORTO THE CROSBY STEAM GAGE AND VALVE COMPANY, OF BOSTON, MASSACHUSETTS.

STEAM-ENGINE PRESSURE-RECORDER AND SPEED-INDICATOR.

SPECIFCATION forming part of Letters Patent No. 316,111, dated April21,1885.

.Application filed August 1I, i884. (No model.)

'o all whom t may concern/,-

Be it known that I, GILMAN WnLD BROWN, of West Newbury, in t-he countyof Essex, ot' the Commonwealth of Massachusetts, haveinvented a new anduseful Improvement in Steam-Engine Pressure-Recorders andSpeedlndicators; and l do hereby declare the same to be described in thefollowing specification and represented in the accompanying draw- I@ings, of which* Figure 1 is a top view, and Fig. 2 a front elevation, ofapressurerecorder and speedindicator provided with my invention. Fig. 3is a vertical section taken through the reciprocating drum and itspaper-carrier and their supporting-arm. Fig. el is an under side view ofthe drum, such ligure showing the cam for operating the angular leverthat carries the pawl for actuating the ratchet-annulus. Fig.

2o 5 is a top View of such ratchet-annulus, its friction-spring, andoperative lever and pawl, and certain parts adjacent thereto.

The steam-engine pressure-recorder to which my invention is applied isof the class or kind generally known by the name of the steampressureindicator or recorder,77 one of such being described in the UnitedStates Patent No. 219,149, granted September 2, 1879, to George H.Crosby, it being to record or mark 3o 0n a sheet of paper by means of apencil a curved line indicative of the varying pressure in the cylinderof a steamengine during a stroke of the piston thereof.

ln the drawings, A denotes the steam-cyl- 3 5 inder of the recorder; e,the piston-rod thereof; B, the niarkercarrying lever, C, thereciprocating drum; D, its paper-carrier or sustaining sleeve, and l?the parallel motion.

The nature of my invention is duly defined 4o in the claimsherereinai'ter presented, the purpose of it being to determine the speedof the piston of the steam-engine or the number of strokes such pistonmay make in .a given period of timeas a minute, for instance. To

this end there is fastened on the arm F, that supports the spindle b ofthe reciprocating drum C, and below such drum, a disk, c, to which isapplied eoncentrically a ratchet ring or annulus, E, provided at itsperiphery with 5o one hundred or any suitable number of teeth,

one hundred being a very convenient number for use.

Upon the upper surface of the said annulus or ring there are divisionsand numbers, as O 10 20 30, Sec., expressive of the number of'teeth inany arc of the circumference of 55 the ratclnt-ring or Hat annulus,extending from the zero of the scale. There projects from the spindleb,and over and upon the hat ratchet-annulus, a friction plate or spring,d, which is to prevent the ring from being accidentally revolved.

On the lower end of the drum C is a scrollcam, e, against whoseperiphery the longer arm of an angular lever, f, rests, there beingpivoted to the shorter arm of such lever a pawl, y, to engage with theteeth ot' the ring. The lever is fulcrumed to the arm F, and has atooth, h, projecting back i'rom it to engage with a lever-latch, t',fulcrumed to the said arm,vand formed and arranged as represented. Aspring, k, iixed to the arm F, bears against the said tooth, in order toforce thelonger arm ofthe leve-r against the periphery ofthe cam. Thelatch, when in engagement with thc tooth, serves to hold the lever offor away from the cam when it may not be desirable to have the annulusrevolved. A spring, l, presses the pawl up to the periphery of theratchet-ring.

As the drum will be partially revolved during each downward or in strokeof the piston ofthe steam-engine, the scroll-cam c will move the angularlever f far enough for it to cause the pawl g to turn the ring theangular distance of one tooth thereof, and therefore if the ring be setwith its Zero-division at the fixed end of the spring 7c, and theleverlatch be moved out of engagement with the tooth ot' the angularlever, such lever will at once be forced into contact with the peripheryofthe scroll-cam. As the drum. maybe reciprocated 9C in a partialrotation by the cord mattached to the piston cross-head or some otherproper movable part of the steam-engine, and to the pulley o of suchdrum, the ratchet-ring will be moved or turned the distance of a toothof it for each downward or in stroke of the en gine-piston. Therefore,by its divisions, such ring will indicate the number of such strokesoccurring in the minute of time commencing at the starting of the ring.During each in` IOO stroke of the piston, the cord a will bc pulled, soas to cause it to turn the drum one way,

the return movement of the drum being effected by a spiral spring, r,applied to it and the spindle in the usual manner.

I herein make no claim to a steam-engine pressure-recorder andspeed-indicator constructed as represented in the United States Patent No. 263,843, granted to the CrosbyT Steam Gage and Valve Company asassignee of myself, theinventor. In my present instrument, although themechanism for recording the pressure ofthe steam is very lik e, if notsubstantially the same as,that shown in the said patent,the mechanismfor indicating the speed of the steam-engine piston or number of itsstrokes is entirely dillerent from anything described and shown in suchpatent, and in no respect performs the office of recording the saidspeed on paper, but simply indicates it, as described, by means of arotary toothed annulus.

I claim in the steam-enginepressure-recorder and speed-indicatorl. Thecombination ofthe divided ratchetannulus, the arm of the recorder, thereciprocating drum, and the cam fixed to the bottom thereof, with anangular lever and its pawl,

such lever being fulcrumed to the said arm and to operate with the cam,and such pawl being to engage with the ratchet-annulus, as set forth,and such lever and pawl having springs for forcing the former againstthe cam and the angularlever and pa-Wl, all being substantially and tooperate as set forth.

GILMAN WELD BROWN. Witnesses:

R. H. EDDY, E. B. PRATT.

